1. Field of the Invention
The present invention relates to a storage method for an electronic still camera which is suitably used in, for example, a digital camera for digitally storing picked-up images.
2. Description of Related Art
In an electronic still camera represented by the conventional digital camera, the creation of image files is performed in accordance with a prescribed format. The format prescribed is as follows.
First, directories for treating images obtained by an electronic still camera are prepared, and therein a “CTG_(four-digit numeral)” directory is created. Here, in respect of the name of the “CTG_(four-digit numeral)” directory, the four-digit numeral starts from 0000 and increases in number in such a manner as to be 0001, 0002, . . . , as the photo-taking operation progresses, and upon overflow of the four digits of the numeral, the four-digit numeral proceeds to a five-digit numeral, becoming “CTG_(five-digit numeral)”.
Then, an “AUT_(four-digit numeral).jpg” file as an image file is created in the above-mentioned “CTG_(four-digit numeral)” directory. In each “CTG_(four-digit numeral)” directory, for example, fifty “AUT_(four-digit numeral).jpg” files at the maximum per directory are created. Incidentally, “THM_(four-digit numeral).jpg” files of a thumbnail image are the same in numeral/number as “AUT_(four-digit numeral).jpg” files.
The reason why the maximum number of image files in one directory is set to fifty, is that, when additionally entering image files into a medium containing one thousand image files, if the upper limit to the number of files of one directory is fifty, the number of directory entries to be retrieved is only twenty, whereas if no limit is placed on the number of files for one folder, the number of directories to be retrieved can be as many as one thousand. Thus, by limiting the number of files in one directory, the ease-of-use of an electronic still camera is improved without increasing the interval of an image pickup action due to the increase in the number of directories to be retrieved.
However, since, in the above-described prior art, the upper limit of the number of files in one directory is set to fifty, there is a possibility that, when photo-taking a combination of serial images as in the case of a continuous shooting mode or a panorama joining image pickup mode, these images may be stored extending over different directories. In such a case, inconveniences have sometimes been caused when rearranging image files after photo-taking or when joining image files obtained by the panorama joining image pickup mode, using an application software program.